[F:1][C:2]1([F:10])[CH2:7][CH2:6][CH:5]([CH2:8]O)[CH2:4][CH2:3]1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C(Br)(Br)(Br)[Br:31]>C(Cl)Cl>[Br:31][CH2:8][CH:5]1[CH2:6][CH2:7][C:2]([F:10])([F:1])[CH2:3][CH2:4]1(4,4-Difluorocyclohexyl)methanol (7.22 g, 48.08 mmol) and triphenylphosphine (25.2 g, 96.16 mmol) were dissolved in DCM (75 mL) and cooled to 0° C. under nitrogen atmosphere. Carbon tetrabromide (31.9 g, 96.16 mmol) was dissolved in DCM (75 mL) and added to the reaction mixture. The mixture was stirred at room temperature overnight. The solvent was evaporated. Pentane (250 mL) was added to the orange residue, which caused triphenylphosphineoxide to precipitate. The off-white solids were filtered off. The filtrate was evaporated and purified on a ISOLUTE Silica Flash column (50 g). Pentane followed by EtOAc:pentane (1% EtOAc) was used as eluent. 4-(Bromomethyl)-1,1-difluorocyclohexane (5.48 g, 54%) was isolated. 1H NMR (400 MHz, cdcl3) δ 1.32-1.46 (m, 2H), 1.64-1.84 (m, 3H), 1.90-1.99 (m, 2H), 2.05-2.18 (m, 2H), 3.31 (d, 2H).
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